// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Junction temperature thermal driver for Maxim Max77620.
   *
   * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
   *
   * Author: Laxman Dewangan <ldewangan@nvidia.com>
   *	   Mallikarjun Kasoju <mkasoju@nvidia.com>

   */
  
  #include <linux/irq.h>
  #include <linux/interrupt.h>
  #include <linux/mfd/max77620.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/platform_device.h>
  #include <linux/regmap.h>
  #include <linux/slab.h>
  #include <linux/thermal.h>
  
  #define MAX77620_NORMAL_OPERATING_TEMP	100000
  #define MAX77620_TJALARM1_TEMP		120000
  #define MAX77620_TJALARM2_TEMP		140000
  
  struct max77620_therm_info {
  	struct device			*dev;
  	struct regmap			*rmap;
  	struct thermal_zone_device	*tz_device;
  	int				irq_tjalarm1;
  	int				irq_tjalarm2;
  };
  
  /**
   * max77620_thermal_read_temp: Read PMIC die temperatue.
   * @data:	Device specific data.
   * temp:	Temperature in millidegrees Celsius
   *
   * The actual temperature of PMIC die is not available from PMIC.
   * PMIC only tells the status if it has crossed or not the threshold level
   * of 120degC or 140degC.
   * If threshold has not been crossed then assume die temperature as 100degC
   * else 120degC or 140deG based on the PMIC die temp threshold status.
   *
   * Return 0 on success otherwise error number to show reason of failure.
   */
  
  static int max77620_thermal_read_temp(void *data, int *temp)
  {
  	struct max77620_therm_info *mtherm = data;
  	unsigned int val;
  	int ret;
  
  	ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
  	if (ret < 0) {
  		dev_err(mtherm->dev, "Failed to read STATLBT: %d
  ", ret);
  		return ret;
  	}
  
  	if (val & MAX77620_IRQ_TJALRM2_MASK)
  		*temp = MAX77620_TJALARM2_TEMP;
  	else if (val & MAX77620_IRQ_TJALRM1_MASK)
  		*temp = MAX77620_TJALARM1_TEMP;
  	else
  		*temp = MAX77620_NORMAL_OPERATING_TEMP;
  
  	return 0;
  }
  
  static const struct thermal_zone_of_device_ops max77620_thermal_ops = {
  	.get_temp = max77620_thermal_read_temp,
  };
  
  static irqreturn_t max77620_thermal_irq(int irq, void *data)
  {
  	struct max77620_therm_info *mtherm = data;
  
  	if (irq == mtherm->irq_tjalarm1)
  		dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred
  ");
  	else if (irq == mtherm->irq_tjalarm2)
  		dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred
  ");

  	thermal_zone_device_update(mtherm->tz_device,
  				   THERMAL_EVENT_UNSPECIFIED);

  
  	return IRQ_HANDLED;
  }
  
  static int max77620_thermal_probe(struct platform_device *pdev)
  {
  	struct max77620_therm_info *mtherm;
  	int ret;
  
  	mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL);
  	if (!mtherm)
  		return -ENOMEM;
  
  	mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
  	mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
  	if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
  		dev_err(&pdev->dev, "Alarm irq number not available
  ");
  		return -EINVAL;
  	}

  	mtherm->dev = &pdev->dev;
  	mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
  	if (!mtherm->rmap) {
  		dev_err(&pdev->dev, "Failed to get parent regmap
  ");
  		return -ENODEV;
  	}

  	/*

  	 * The reference taken to the parent's node which will be balanced on
  	 * reprobe or on platform-device release.

  	 */

  	device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);

  	mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
  				mtherm, &max77620_thermal_ops);
  	if (IS_ERR(mtherm->tz_device)) {
  		ret = PTR_ERR(mtherm->tz_device);
  		dev_err(&pdev->dev, "Failed to register thermal zone: %d
  ",
  			ret);
  		return ret;
  	}
  
  	ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL,
  					max77620_thermal_irq,
  					IRQF_ONESHOT | IRQF_SHARED,
  					dev_name(&pdev->dev), mtherm);
  	if (ret < 0) {
  		dev_err(&pdev->dev, "Failed to request irq1: %d
  ", ret);
  		return ret;
  	}
  
  	ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL,
  					max77620_thermal_irq,
  					IRQF_ONESHOT | IRQF_SHARED,
  					dev_name(&pdev->dev), mtherm);
  	if (ret < 0) {
  		dev_err(&pdev->dev, "Failed to request irq2: %d
  ", ret);
  		return ret;
  	}
  
  	platform_set_drvdata(pdev, mtherm);
  
  	return 0;
  }
  
  static struct platform_device_id max77620_thermal_devtype[] = {
  	{ .name = "max77620-thermal", },
  	{},
  };

  MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);

  
  static struct platform_driver max77620_thermal_driver = {
  	.driver = {
  		.name = "max77620-thermal",
  	},
  	.probe = max77620_thermal_probe,
  	.id_table = max77620_thermal_devtype,
  };
  
  module_platform_driver(max77620_thermal_driver);
  
  MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
  MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
  MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
  MODULE_LICENSE("GPL v2");